Siemens QF240A NN 2 Pole Molded Case Circuit Breaker

Siemens QF240A NN 2-Pole Molded Case Circuit Breaker is a two-pole, 40-amp molded-case protective device in Siemens’ QF family. Rated for 120/240 V AC and designed as a plug-in ground-fault circuit interrupter (GFCI) breaker, it provides branch-circuit protection with ground-fault sensing to help prevent electric shock on circuits where GFCI is required. It employs a thermal-magnetic trip mechanism and offers a 10 kA interrupting rating at 240 V, delivering reliable protection against overcurrent and short circuits in residential and light commercial installations. This model is intended for use in compatible Siemens panels with QF-type plug-in mounting. The 2P configuration allows protection of both hot legs on a split-phase circuit, making it suitable for 120/240 V circuits typical in homes and small businesses. When GFCI protection is mandated by code, the QF240A NN serves as a dedicated solution that combines sensing, quick-trip action, and compact molded-case construction for easy replacement in existing panels.